1. Field of the Invention
The invention relates to a guide rail for accommodating movement of at least one openable roof part of a motor vehicle, the guide rail having at least one first and one second guide rail section which can be joined to one another via a joint, the first and the second guide rail section being movable into alignment at the joint and the openable roof part can be movable beyond the joint.
2. Description of Related Art
German Patent Nos. DE 42 03 229 C2 and DE 43 26 291 C2 and their corresponding U.S. Pat. No. 5,558,388 disclose a guide rail in which first guide rail sections are located in the side members in which the openable roof part can be moved in the lengthwise direction of the motor vehicle into various open positions, and the side members are pivotally coupled to a rear roof part, detachably connected to a front cross beam which runs above the windshield, and after unlocking from the front cross beam they can be swung onto the rear roof part. In the rear roof part, there are two guide rail sections which support the openable roof part in the open position.
The entire motor vehicle roof including the rear window which is connected to the rear roof part can be lowered, to create a convertible-like roof opening, into a stowage space in the rear part of the motor vehicle by means of a mechanism which comprises several drives. In the front cross beam, there is an electric drive which effects unlocking of the side members from the cross beam, a second electric drive in the rear roof part undertakes displacement of the openable roof part and another electric drive which is likewise attached in the area of the rear roof part is used to swivel the side members. Furthermore, there is a hydraulic cylinder in the area of the rear motor vehicle side walls which provides for pivoting of the rear roof part together with the openable roof part which is held by the rear roof part, the side members which are pivoted onto the rear roof part, and rear columns (C-columns) on which the rear roof part rests on both sides.
One fundamental problem in divided guide rails lies in the moving of two or more guide rail sections into alignment at the joints, and in doing so, achieving serviceable tolerances.
Conventionally, this is done by the guide rail sections being attached via detachable mechanical connecting elements, for example, by means of screws, to the roof parts which support or accommodate them, for which time-consuming, and thus expensive, adjustment efforts become necessary. In doing so, the accessibility of the screw sites must be ensured; this generally necessitates additional cover parts, by which not only limitations in the optical appearance, but also other costs for parts and installation arise.
The primary object of the present invention is to devise a guide rail of the initially mentioned type in which the guide rail sections can be brought into alignment without complex adjustment efforts, and the guide rails can be universally used.
This object is achieved via a guide rail with at least one first and one second guide rail section which can be joined to one another via a joint and which can be moved into alignment with one another at the joint, the openable roof part being movable beyond the joint, by the first guide rail section comprising a centering element or one being fixed on it, which interacts with a complementary opposite element on the second guide rail section or is fixed on it, the first and/or the second guide rail section being flexibly supported at least in the area of the joint on a roof part of the motor vehicle.
By the centering element interacting with the opposite element when the guide rail sections are brought together, via the support of the first and/or second guide rail section on the roof part, the support being made flexible at least in the area of the joint, the guide rail sections are brought into alignment, and parts tolerances, especially tolerances of the roof part which support the guide rail section, are equalized. When the guide rail sections are brought together, the tolerances at the joint are determined essentially only by the centering element and the opposite element, eliminating the need for complex adjustment efforts.
Preferably, the centering element and the opposite element are made such that, when the first and the second guide rail section are joined or brought together, alignment errors between the guide rail sections can be equalized by linear elastic displacement of the end of the first and/or the second guide rail section facing the joint in the directions perpendicular to the displacement direction of the openable roof part.
The centering element and the opposite element are furthermore made such that, when the first and the second guide rail section are brought together or connected, alignment errors between the guide rail sections can be equalized by elastic tilting of the end of the first and/or the second guide rail section facing the joint around an axis which runs essentially in the displacement direction of the openable roof part.
The flexible support can be made such that the flexibility is greatest in the area of the joint and decreases with increasing distance from the joint, and the first and/or the second guide rail section can be rigidly connected to the roof part in the area of its end facing away from the joint. In particular, the first and/or the second guide rail section over roughly 20 to 40% of its total length, proceeding from its end facing away from the joint, is rigidly connected to the roof part, for example, via mechanical connecting elements, such as rivets or screws. Preferably, roughly one third of the guide rail section is rigidly connected to the roof part.
In another embodiment of the intention, the area of the first and/or the second guide rail section which extends between the joint and the area of the guide rail section which is rigidly connected to the roof part is guided freely in or on the roof part. In this way, the bending elasticity of the guide rail section itself can be used to achieve flexibility of the two guide rail sections with reference to one another in the area of the joint.
If the first and/or the second guide rail section are supported in the area of the joint via a rubber-elastic intermediate element on the roof part, rattling noise can be avoided and effective vibration damping can be achieved. Furthermore, it is possible to also support the entire guide rail section flexibly or floating, for example, by its being connected to the roof part solely via the rubber elastic intermediate elements and a rigid connection of its end facing away from the joint to the roof part being eliminated.
The centering element can comprise a centering journal and the opposing element can comprise a centering bearing, and the centering journal can be inserted into the centering bearing, preferably, essentially perpendicularly with respect to the plane which comprises the joint.
The centering bearing can be made such that it comprises an insertion section which advantageously faces the joint and a centering section, the insertion section tapering towards the centering section and the centering journal being accommodated free from play in the centering section.
The alignment tolerances with the guide rail sections brought together can be reduced if the centeringjoumal can be brought into linear contact with the centering section of the centering bearing.
If the centering journal has a non-round cross section at least in the area of its play-free accommodation in the centering section, the centering journal is prevented from being able to turn in the centering bearing. This ensures not only centering or alignment of the two guide rail sections in directions essentially perpendicular to the direction of insertion of the centering journal into the centering bearing, but also prevents pivoting of the two sections around an axis which runs in the insertion direction. Here, the centering journal in the area of its play-free accommodation in the centering section, preferably, has a cross section which is essentially rectangular.
The insertion of the centering journal into the centering bearing and its defined contact in the centering section can be improved by the centering journal being elongated proceeding from its area of play-free accommodation in the centering section essentially in and against its insertion direction into the centering bearing and by its tapering in the two directions.
The centering bearing can be easily and economically produced even with a complex geometry if it is made as a plastic part and is injected onto the second guide rail section in the area of the joint.
In another embodiment of the invention, the centering element can comprise at least one second centering journal and the opposite element can comprise at least one second centering bearing, and the second centering journal can be inserted into the second centering bearing. By providing two centering journals and centering bearings which can be made fundamentally the same, especially alignment errors as a result of tilting or twisting of the guide rail sections around an axis placed in the displacement direction of the openable roof part are reduced.
It is possible for the second centering journal and the second centering bearing to be made less complex than the first centering journal and the first centering bearing. In particular, the second centering journal can be made as a centering strip which is fixed in the first guide rail section and projects above the joint, and it can be inserted into the second centering bearing which is molded onto the second guide rail section, preferably in one piece. Here, the first and/or the second guide rail section is preferably made as a metallic extrusion.
The first and the second guide rail section can fundamentally be completely separable from one another. Alternatively or in combination therewith the guide rail sections can be pivoted at the joint with reference to one another, for example, similarly to the type known from DE 42 03 229 A1 and corresponding U.S. Pat. No. 5,558,388.
The first or second guide rail section can be located especially on a roof part which is connected detachably to the motor vehicle and which supports the openable roof part in its open position.
Furthermore, the first or second guide rail section can be located on the side members which extend in the displacement direction of the openable roof part, and the side members can also be detachably connected to the motor vehicle.
In the following, advantageous embodiments of the subject matter of the invention are explained using the drawings: